That giant sucking sound you heard Tuesday was white America gasping with the announcement that a Los Angeles jury had cleared O.J. Simpson of murder charges. That outburst of joy was black America celebrating.

An oversimplification, to be sure. But there may have been no single moment in American history when the gulf between black and white Americans was so visibly, audibly apparent as that moment, shortly after 10 a.m. Los Angeles time, when the trial of the century came to its sudden, stunning conclusion.

Visibly, audibly and viscerally.

Here were millions of white Americans feeling in the pits of their stomachs an ominous, sinking feeling. It was a feeling of disappointment and dread made all the more sickly and disturbing by the heights of exhilaration to which their spirits had been lifted by the surprise overnight expectation that somehow, miraculously, the chasm of race had been crossed, that a mostly black jury had recognized the rancid racism of Los Angeles Police Officer Mark Fuhrman and yet still convicted O.J. Simpson of the crime that seemed to so many whites as obvious as the videotaped beating of Rodney King by members of that same police department only three years before.

And here were millions of their fellow Americans, African-Americans who, based on the very same set of facts, were feeling the adrenalin rush of victory and pride.

“I think it’s important that every now and then we have a victory,” said William H. Grier, a black psychiatrist in San Diego and co-author the 1968 classic, “Black Rage,” who was delighted with Tuesday’s outcome.

“Johnnie Cochran is our hero,” said Grier. The very different reactions to the verdict, Grier said, were, in concentrate, the black-white reaction to Cochran’s controversial closing in which he called on the mostly black jury to strike a blow against racism by exonerating Simpson.

“When Cochran gave his closing, I don’t know of a single black who didn’t feel like standing up and cheering,” said Grier. “And I don’t know a single white who didn’t think he sounded like some snake-oil salesman.”

That America has a problem with race, that blacks and whites experience America and, in particular the American criminal justice system, in ways that are as different as, well, black and white, is not news.

But, what a year or more of Simpson, from the low-speed chase to the lightning-fast deliberations, have done is enshrine this basic insight about the difference in black and white realities as perhaps the central dilemma-cum-cliche of American race relations.

It is especially not news to blacks, who have had to live day to day, generation to generation with that tawdry alternate reality that whites could not see or feel or believe, and could discount as regrettable but aberrational when they were forced to confront the behavior of Los Angeles police officers like Fuhrman or Stacey Koon (remember Rodney King?).

“You ask whites, `What does it mean being white,’ and they say, `I never thought about it much.’ Being white is like being part of the woodwork,” says sociologist Joe Feagin, the co-author of “White Racism,” and “Living with Racism.”

But, Feagin, who is white, said “you ask any non-white person about race and they have ready answers.”

To Feagin, the glory of the Simpson case to the black community is that here, finally, was a black man with the money and celebrity to be able to expose the racism endemic to the criminal justice system, and expose it in time to save himself.

To those whites who ask what are the odds of police conspiring to frame O.J. Simpson, there are blacks who can respond what are the odds of a “genocidal racist” as Johnnie Cochran called Fuhrman, just stumbling upon this case.

“What O.J.’s money got him was the kind of trial that affluent whites get routinely in this society. With a poor black, this trial would have been over in two or three days,” said Feagin.

“It’s very healthy for the black community. As an African-American you can say, `Gee, the criminal justice system may be getting better, or at least you can sometimes get a fair verdict if you have enough money,” said Feagin.

And Feagin believes the jury had ample reason for reasonable doubt far more than the Simi Valley jury, which without any blacks among its numbers, acquitted the police officers who beat Rodney King, precipitating the Los Angeles riots in 1992. “I would say he’s not guilty because they cannot say he’s guilty beyond a reasonable doubt,” said Feagin.

But to historian, writer and activist Roger Wilkins, who is black and was troubled by the Simpson jury’s swift acquittal, the verdict was ” the mirror image of the Simi Valley verdict.”

“Both juries were responding to some of the deepest primal fears that their tribe holds for the other,” said Wilkins. “Whites were fearful of untamed black violence, and blacks were afraid of the ruthless and relentless use of white power to cut down blacks, particularly those who are high achievers.”

And so Wilkins may have been among a minority of blacks who watched yesterday’s outcome with some alarm. “I see it as a much more powerful indication of how divided we are than the polls which were showing how differently blacks and whites viewed Simpson’s guilt or innocence,” he said.